324 SANITARY ENTOMOLOGY 



4). Hot Air Delousmg 



Hpt air was used very extensively for delousing the armies, especially 

 on the eastern front. This system is not sterilizing, nor is it especially 

 dangerous to the garments except when allowed to get too hot. Stagnant 

 hot air has less effect than fresh hot air. The garments must be hung 

 loosely. Provision should be made for circulating the air so that all of 

 the clothes will receive the necessary amount of heat, which is 131° F, 

 (55° C.) for 30 minutes, or 140° F. (60° C.) for 15 minutes. The heat 

 chamber may be a portable box such as a fireless cooker; a room heated 

 by steam pipes or hot air ; a sod hut ; a steel autoclave ; or an improvised 

 oven, Very high heat must not be used on dry garments as it will dis- 

 integrate the fibers of woolens and cause shrinkage. 



5. Fumigation 



When fumigation chambers are available and the clothing is needed for 

 immediate wear, this is one of the quickest means of delousing. The 

 fumigation chamber may be : 



a. A room, with cracks tightly sealed, and with vestibuled doors. 

 A sign of warning should be posted and the door kept locked during fumi- 

 gations. Only persons understanding fumigation should be permitted 

 around, and they should wear gas masks. 



b. A chest or box is sufficient for carbon bisulphide or chlorpictin. 



c. A portable unit, such as an automobile with an air-tight chamber, 

 and with hangers or shelves. The gas generator may be placed behind 

 the chauffeur's seat. 



d. A vacuum chamber as in steam sterilization. The same cylinder 

 may be made available for either steam or gas. 



The fumigation may be either at normal atmospheric pressure or 

 in a vacuum. When a room is to be fumigated one should see that there 

 are no persons in the building, as few buildings are constructed so that 

 the gas can not penetrate to other rooms. 



To fumigate an entire building, or a room, close tightly all openings 

 in building and seal up cracks with paper, unless the insects are in 

 the double walls, in which case seal the cracks on the outside. It may 

 be necessary, if the building is too loosely constructed, to increase dosages 

 or make a tarpaulin to cover the entire structure. Such measures should 

 only be taken in case the normal fumigation is unsuccessful. Any of 

 the following methods are practicable. Entomologists prefer cyanide 

 but many army officials prefer sulphur. 



a. Sulphur corrodes metal, so all movable metal should be taken out 

 of the building. Sulphur fumigation is described in Public Health Bull. 



